All,

I have an 18F22K20 on a board with a 10K pullup and a GLCD.  There is =20
decoupling for the chip.  My programmer is a PK2 clone that I've never =20
had other problems with.

I can program/verify the chip fine using the PICKit2 software, but =20
when it comes to releasing MCLR the code doesn't run.  I struggled =20
with this for a while until I found that power cycling the board =20
(disconnect from 3.3v and reconnect) kicks it into life, every time.  =20
The code then runs as expected.

This is true even if the ICSP connection is still made to the =20
programmer.  As soon as MCLR is entered (any activity by the =20
programmer) it's back to not running.

The only "unusual" thing on the board is that one of PGC or PGD is =20
shared with the cathode from a backlight LED that the PIC sinks.  But =20
this connection doesn't need to be removed for the PIC to run.

Are there any obvious reasons why the chip would fail to leave MCLR?  =20
I can live with power cycling the board to get it working, but it's a =20
bit of a pain.

David
--=20
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